JP2002047414A - Heat-resistant resin composition, coating material and enamel wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyamideimide based heat-resistant resin composition having excellent wear resistance and flexibility, a coating material which uses this heat-resistant resin composition as the film-forming component, and an enamel wire having excellent wear resistance and flexibility which uses this coating material. SOLUTION: The heat-resistant resin composition comprises a polyamideimide resin and a heterocyclic mercaptan represented by formula (I) (wherein A is a group to form a 5 or 6-memebered hetero ring together with a group of formula (II) and has a main chain composed of two or three carbon atoms bonded by a single bond or a double bond, two or three carbon atoms forming a part of one aromatic ring, two nitrogen atoms bonded by a single bond or a double bond, or one carbon atom and one or two nitrogen atoms bonded by a single bond or a double bond; and X is oxygen atom, sulfur atom, carbon atom or nitrogen atom and the carbon atom or the nitrogen atom is substituted with hydrogen atom, a 1-4C alkyl group, phenyl group or mercapto group). The coating material and the enamel wire use this heat-resistant resin composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-resistant resin composition and a paint suitable as a varnish for an enameled wire and the like, and an enameled wire using the same.

[0002]

2. Description of the Related Art Polyamide imide resin is widely used as a coating agent for various substrates because of its excellent heat resistance, chemical resistance and solvent resistance.
Used as heat-resistant paint.

[0003] In recent years, electric manufacturers using enameled wires have introduced automatic high-speed winding machines in order to streamline the manufacturing process of the equipment. Mechanical damage to the wire insulation layer,
There is a problem that a layer short-circuit, a ground defect, and the like occur, thereby increasing a product defect rate. Therefore, there is a demand for an enameled wire with less mechanical damage.

[0004] The conventional polyamide-imide wire is superior in mechanical strength to other polyester and polyester-imide wires.
Polyamideimide resins obtained by the reaction of 4,4'-diphenylmethane diisocyanate with trimellitic anhydride have been applied in a single-layer or multilayer structure.

However, in recent years, the speed of the winding machine has been further increased and the winding process has become more complicated, and the polyamideimide resin cannot sufficiently cope with the above.

[0006]

DISCLOSURE OF THE INVENTION The present invention relates to a polyamideimide heat-resistant resin composition having excellent abrasion resistance and flexibility, a paint containing the heat-resistant resin composition as a coating film component, and a paint using the same. An object of the present invention is to provide an enameled wire having excellent wear resistance and flexibility.

[0007]

DISCLOSURE OF THE INVENTION The present invention relates to a polyamideimide resin and a compound of the formula (I)

[0008]

Embedded image (Where A is a group

[0009]

Embedded image Is a group which forms a heterocyclic ring composed of 5 or 6 atoms together with a single bond or a double bond.
Or three carbon atoms, two or three carbon atoms forming part of one aromatic ring, two nitrogen atoms connected by a single or double bond, or One carbon atom connected by a bond or a double bond to one
Has a main chain of one or two nitrogen atoms, and X is an oxygen atom, a sulfur atom, a carbon atom or a nitrogen atom, wherein the carbon atom or the nitrogen atom is a hydrogen atom,
Which is substituted with an alkyl group, a phenyl group or a mercapto group).

The present invention also relates to a polyamide-imide resin
The present invention relates to the heat-resistant resin composition containing 0.01 to 20 parts by weight of the heterocyclic mercaptan represented by the general formula (I) based on 0 parts by weight.

[0011] The present invention also relates to a heat-resistant resin composition wherein the polyamideimide resin has a number average molecular weight of 10,000 to 50,000.

[0012] The present invention also relates to a paint comprising the heat-resistant resin composition as a coating film component.

[0013] The present invention also relates to an enameled wire formed by using the paint to form a film.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The polyamideimide resin used in the heat-resistant resin composition of the present invention preferably has a number average molecular weight of 10,000 to 50,000 as described above. When the number average molecular weight is less than 10,000,
When formed into a coating, the film forming property tends to be poor,
If it exceeds 000, the viscosity increases when dissolved in a solvent at an appropriate concentration as a coating, and the workability during coating tends to be poor. For this reason, it is more preferable that the number average molecular weight of the polyamideimide resin be 10,000 to 25,000.

The number average molecular weight of the polyamideimide resin is sampled at the time of resin synthesis, measured by gel permeation chromatography (GPC) using a standard polystyrene calibration curve, and measured until the desired number average molecular weight is reached. The composition is controlled within the above range by continuing the synthesis.

The polyamide-imide resin used in the present invention has, for example, a repeating structural unit represented by the general formula (II).

[0017]

Embedded image (In the formula, R ¹ represents a trivalent organic group, R ² represents a divalent organic group, and n represents a positive integer.) A typical method for synthesizing such a polyamideimide resin is as follows. Examples include 1) a method of reacting diisocyanate with tribasic acid anhydride, (2) a method of reacting diamine with tribasic acid anhydride, and (3) a method of reacting diamine with tribasic acid chloride. However, the method for synthesizing the polyamideimide resin used in the present invention is not limited to these methods.

Representative compounds used in the above synthesis method are listed below.

First, as the diisocyanate, 4,
Preferred examples include 4'-diphenylmethane diisocyanate, xylylene diisocyanate, 3,3'-diphenylmethane diisocyanate, 4,4'-diphenyl ether diisocyanate, 3,3'-diphenyl ether diisocyanate, and paraphenylene diisocyanate.

Examples of the diamine include 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 4,4'-diaminodiphenylether,
Preferred are 3,3'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, xylylenediamine, phenylenediamine and the like.

Among these, 4,4'-diphenylmethane diisocyanate, 3,3'-diphenylmethane diisocyanate, 4,4'-diphenyl ether diisocyanate, 3,3'-diphenyl ether diisocyanate, 4,4'-diaminodiphenyl ether,
3'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, and 3,3'-diaminodiphenylmethane are more preferred.

As the tribasic acid anhydride, trimellitic anhydride is mentioned as a preferable one, and as the tribasic anhydride chloride, trimellitic anhydride chloride and the like are mentioned.

In synthesizing the polyamideimide resin, dicarboxylic acid, tetracarboxylic dianhydride and the like can be simultaneously reacted within a range that does not impair the properties of the polyamideimide resin.

The dicarboxylic acids include terephthalic acid, isophthalic acid, adipic acid and the like. The tetracarboxylic dianhydrides include pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, biphenyl tetracarboxylic dianhydride. Anhydrides and the like. These are preferably used at 50 equivalent% or less of the total acid components.

The heat-resistant resin composition of the present invention contains a heterocyclic mercaptan represented by the general formula (I) together with the above polyamideimide resin. By using this compound, the adhesion can be improved and excellent wear resistance can be obtained. The amount of the heterocyclic mercaptan represented by the general formula (I) is 100
It is preferably 0.01 to 20 parts by weight based on parts by weight. When the amount is less than 0.01 part by weight, the effect of improving the adhesion becomes small, and when it exceeds 20 parts by weight, the heat resistance of the coating film tends to gradually decrease. From this, the blending amount of the heterocyclic mercaptan represented by the general formula (I) is 0.00.0 parts by weight based on 100 parts by weight of the polyamideimide resin.
More preferably 5 to 10 parts by weight, and 0.1 to 8 parts by weight.
It is particularly preferred to use parts by weight.

The heterocyclic mercaptan represented by the general formula (I) is not particularly limited and may be 2-amino-5-
Compounds having a thiadiazole skeleton such as mercapto-1,3,4-thiadiazole (A: -C (NH ₂ ) = N
-, X: S), 1-phenyl-5-mercapto-1,
Compounds having a tetrazole skeleton such as 2,3,4-tetrazole and 1-methyl-5-mercapto-1,2,3,4-tetrazole (A: -N = N-, X: N-Me, N
-Ph), 2-mercapto imidazoline, etc. compound having an imidazoline skeleton of _{(A: -CH 2 CH 2 -} , X: N
H), compounds having a benzothiazole skeleton such as 2-mercaptobenzothiazole and 2-mercaptobenzothiazolecyclohexylamine salt (A: C ₆ H ₄ , X:
S), compounds having a triazine skeleton such as 2-di-n-butylamino-4,6-dimercapto-1,3,5-triazine and 2,4,6-trimercapto-1,3,5-triazine ( _{A: -N = C (C 4} H 8 NH 2) -N-,
-N = CH-N-, X: C-SH) and the like.
Among them, a compound having a thiadiazole skeleton, a compound having a benzothiazole skeleton, and a compound having a triazine skeleton are preferable, and 2-amino-5-mercapto-1,
3,4-Thiadiazole, 2-mercaptobenzothiazolecyclohexylamine salt, 2-di-n-butylamino-4,6-dimercapto-1,3,5-triazine are most preferred.

The compound having a mercapto group can be mixed with a polyamideimide resin as a solution dissolved in a basic polar solvent. As the basic polar solvent, N-methyl-2-pyrrolidone, N, N-dimethylformamide and the like can be used. The concentration of the solution is not particularly limited. For example, 100 parts by weight of the heterocyclic mercaptan represented by the general formula (I) is added to a basic polar solvent 9
It is preferable to dissolve it in 00 to 4000 parts by weight before use.

The method for blending the heterocyclic mercaptan represented by the general formula (I) is not limited to this, and other methods can be applied as appropriate.

The heat-resistant resin composition of the present invention comprises a polar solvent such as N-methyl-2-pyrrolidone and N, N'-dimethylformamide, an aromatic hydrocarbon solvent such as xylene and toluene, methyl ethyl ketone, methyl isobutyl ketone and the like. Can be dissolved in a solvent such as ketones and adjusted to an appropriate viscosity to obtain a coating. When used as a paint, the solid content is generally 10 to 50% by weight.

The coating material obtained is applied to the object to be coated and cured to form a coating film having excellent abrasion resistance and flexibility on the surface of the object to be coated. Examples of the object to be coated include a metal wire such as a copper wire, and an enamel wire having excellent wear resistance and flexibility can be obtained by applying and baking the paint.

[0031]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples of the present invention and Comparative Examples thereof, but the present invention is not limited to these Examples.

Example 1 255,4'-diphenylmethane diisocyanate
0 g (1.02 mol), trimellitic anhydride 192.0
g (1.00 mol) and N-methyl-2-pyrrolidone 6
60 g was charged into a 2 liter flask, the temperature was increased to 130 ° C. in about 3 hours with stirring, and the temperature was maintained at this temperature for 5 hours to obtain a polyamideimide resin solution having a number average molecular weight of 22,200.

The obtained polyamideimide resin solution 100
Parts by weight (resin concentration: 30% by weight) were N-methyl- of 2-amino-5-mercapto-1,3,4-thiadiazole.
A coating material was obtained by adding 4.0 parts by weight of a 2-pyrrolidone solution (solid content concentration: 20% by weight).

Example 2 200.0 g of 4,4'-diaminodiphenyl ether
(1.00 mol), 192.0 g of trimellitic anhydride
(1.00 mol), N-methyl-2-pyrrolidone 904
g and 4.0 g of boric acid were charged into a 2 liter flask, the temperature was increased to 200 to 205 ° C. in about 3 hours with stirring, and the temperature was kept at this temperature for 12 hours to obtain a polyamideimide resin solution. The number average molecular weight of the obtained polyamideimide resin was 22,500.

The obtained polyamideimide resin solution 100
10 parts by weight of an N, N-dimethylformamide solution of 2-amino-5-mercapto-1,3,4-thiadiazole (solids concentration 5% by weight) was added to parts by weight (resin concentration 35% by weight) to prepare a coating. Obtained.

Example 3 4,4'-diphenylmethane diisocyanate 252.
5 g (1.01 mol), trimellitic anhydride 192.0
g (1.00 mol) and N-methyl-2-pyrrolidone 6
60 g was charged into a 2 liter flask, the temperature was increased to 130 ° C. in about 3 hours with stirring, and the temperature was maintained at this temperature for 5 hours to obtain a polyamideimide resin solution having a number average molecular weight of 21,200.

The obtained polyamideimide resin solution 100
A coating was obtained by adding 3.0 parts by weight of an N-methyl-2-pyrrolidone solution of 2-mercaptoimidazoline (solids concentration: 20% by weight) to parts by weight (resin concentration: 30% by weight).

Example 4 200.0 g of 4,4'-diaminodiphenyl ether
(1.00 mol), 192.0 g of trimellitic anhydride
(1.00 mol), N-methyl-2-pyrrolidone 728
g and 4.0 g of boric acid were charged into a 2 liter flask, the temperature was increased to 200 to 205 ° C. in about 3 hours with stirring, and the temperature was kept at this temperature for 12 hours to obtain a polyamideimide resin solution. The number average molecular weight of the obtained polyamideimide resin was 22,500.

The obtained polyamideimide resin solution 100
10 parts by weight of an N, N-dimethylformamide solution of 2-mercaptoimidazoline (solids concentration 3% by weight) was added to parts by weight (resin concentration 35% by weight) to obtain a coating material.

Example 5 4,4'-Diphenylmethane diisocyanate 255.
0 g (1.02 mol), trimellitic anhydride 192.0
g (1.00 mol) and N-methyl-2-pyrrolidone 6
60 g was charged into a 2 liter flask, the temperature was increased to 130 ° C. in about 3 hours with stirring, and the temperature was kept at this temperature for 4 hours to obtain a polyamideimide resin solution having a number average molecular weight of 23,100.

The obtained polyamideimide resin solution 100
N-methyl-2- of 2,4,6-trimercapto-1,3,5-triazine is added to parts by weight (resin concentration: 30% by weight).
A coating was obtained by adding 4.0 parts by weight of a pyrrolidone solution (solid content concentration: 10% by weight).

Example 6 200.0 g of 4,4'-diaminodiphenyl ether
(1.00 mol), 192.0 g of trimellitic anhydride
(1.00 mol), N-methyl-2-pyrrolidone 904
g and 4.0 g of boric acid were charged into a 2 liter flask, the temperature was increased to 200 to 205 ° C. in about 3 hours with stirring, and the temperature was kept at this temperature for 12 hours to obtain a polyamideimide resin solution. The number average molecular weight of the obtained polyamideimide resin was 22,500.

The obtained polyamideimide resin solution 100
10 parts by weight of an N, N-dimethylformamide solution of 2,4,6-trimercapto-1,3,5-triazine (solids concentration 5% by weight) to 10 parts by weight (resin concentration 20% by weight) and paint I got

Example 7 4,4'-diphenylmethane diisocyanate 255.
0 g (1.02 mol), trimellitic anhydride 192.0
g (1.00 mol) and N-methyl-2-pyrrolidone 6
60 g was charged into a 2 liter flask, the temperature was increased to 130 ° C. in about 3 hours while stirring, and the temperature was maintained at this temperature for 6 hours to obtain a polyamideimide resin solution having a number average molecular weight of 23,000.

The obtained polyamideimide resin solution 100
N-methyl-cyclohexylamine salt of 2-mercaptobenzothiazole was added to parts by weight (resin concentration: 30% by weight).
2-Pyrrolidone solution (solid content concentration 10% by weight) 10.0
The coating was obtained by adding parts by weight.

Example 8 200.0 g of 4,4'-diaminodiphenyl ether
(1.00 mol), 192.0 g of trimellitic anhydride
(1.00 mol), N-methyl-2-pyrrolidone 904
g and 4.0 g of boric acid were charged into a 2 liter flask, the temperature was increased to 200 to 205 ° C. in about 3 hours with stirring, and the temperature was maintained at this temperature for 11 hours to obtain a polyamideimide resin solution. The number average molecular weight of the obtained polyamideimide resin was 23,500.

The obtained polyamideimide resin solution 100
20 parts by weight of an N, N-dimethylformamide solution of a cyclohexylamine salt of 2-mercaptobenzothiazole (solids concentration: 5% by weight) was added to parts by weight (resin concentration: 30% by weight) to obtain a paint.

Example 9 4,4'-diphenylmethane diisocyanate 255.
0 g (1.02 mol), trimellitic anhydride 192.0
g (1.00 mol) and N-methyl-2-pyrrolidone 6
60 g was charged into a 2 liter flask, the temperature was increased to 130 ° C. in about 3 hours while stirring, and the temperature was maintained at this temperature for 6 hours to obtain a polyamideimide resin solution having a number average molecular weight of 23,000.

The obtained polyamideimide resin solution 100
Parts by weight (resin content 30% by weight) in N-methyl-2-pyrrolidone solution of 2-di-n-butylamino-4,6-dimercapto-1,3,5-triazine (solid content 10%).
1% by weight) to obtain a paint.

Example 10 200.0 g of 4,4'-diaminodiphenyl ether
(1.02 mol), 192.0 g of trimellitic anhydride
(1.00 mol) and N-methyl-2-pyrrolidone 90
4 g and 4.0 g of boric acid were charged into a 2 liter flask, the temperature was increased to 200 to 205 ° C. in about 3 hours with stirring, and the temperature was kept at this temperature for 11 hours to obtain a polyamideimide resin solution. The number average molecular weight of the obtained polyamideimide resin was 23,500.

The obtained polyamideimide resin solution 100
N-N-N-dimethylformamide solution of 2-di-n-butylamino-4,6-dimercapto-1,3,5-triazine (solid content of 5 parts by weight)
(% By weight) to obtain a paint.

COMPARATIVE EXAMPLE 1 4,4'-Diphenylmethane diisocyanate 255.
0 g (1.02 mol), trimellitic anhydride 192.0
g (1.00 mol) and N-methyl-2-pyrrolidone 6
60 g was charged into a 2 liter flask, the temperature was increased to 130 ° C. in about 3 hours with stirring, and the temperature was maintained at this temperature for 4 hours to obtain a polyamideimide resin. The number average molecular weight of the obtained polyamideimide resin was 20,100. This solution was directly used as a paint.

Comparative Example 2 20,4 g of 4,4'-diaminodiphenyl ether
(1.00 mol), 192.0 g of trimellitic anhydride
(1.00 mol) and N-methyl-2-pyrrolidone 90
4 g and 4.0 g of boric acid were charged into a 2 liter flask, the temperature was increased to 200 to 205 ° C. in about 3 hours with stirring, and the temperature was kept at this temperature for 12 hours to obtain a polyamideimide resin solution. The number average molecular weight of the obtained polyamideimide resin was 22,500. This solution was directly used as a paint.

Test Example The polyamide imide resin solutions obtained in Examples 1 to 10 and Comparative Examples 1 and 2 were applied to a copper wire having a diameter of 1.0 mm according to the following baking conditions, and baked. Was manufactured. [Baking conditions] Number of coating: 8 dice Baking furnace: hot-air vertical furnace (furnace length: 5 m) Furnace temperature: inlet / outlet = 320 ° C / 430 ° C Linear speed: 16 m / min The appearance was good. The properties of each enameled wire coating were tested by the following methods, and the results are shown in Table 1. (1) Flexibility: Checked according to JIS C3003.8.1 (1). (2) Pinhole: Investigated according to JIS C3003.36. (3) Dielectric breakdown voltage: JIS C300 3.11.
The examination was performed according to (2). (4) Reciprocating abrasion resistance: old JIS C3003.10.
Investigation was conducted according to 1. (5) Unidirectional abrasion resistance: Performed according to JIS C3003.10. (6) Softening temperature: Performed according to JIS C3003.12 (2).

[0055]

[Table 1] From the results shown in Table 1, the enameled wire obtained using the polyamide-imide resin composition of the present invention (Examples 1 to 10)
It can be seen that is superior to those of Comparative Examples 1 and 2 in abrasion resistance, and has almost the same flexibility and softening resistance.

[0056]

By using the heat-resistant resin composition and paint of the present invention, a coating film having good wear resistance and flexibility can be formed, and it can be used as an insulating film or a protective coat on various substrates. It is useful, and in particular, can be suitably used for recent severe winding, processing, and assembling operations of enameled wires and the like.

The enameled wire of the present invention is excellent in abrasion resistance and flexibility.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01B 3/30 H01B 3/30 M 7/02 7/02 A (72) Inventor Seiichi Yotsuya Ibaraki 4-13-1, Higashimachi, Hitachi City Hitachi Chemical Co., Ltd. Yamazaki Office F-term (reference) 4J002 CM041 EV016 FD146 GH01 GQ01 4J038 DJ051 JC02 MA14 NA11 NA12 NA21 PB09 PC02 5G305 AA02 AA11 AB15 AB17 BA09 BA26 CA24 CB15 CB19 CB25 MA03

Claims (8)

[Claims] 1. A polyamide-imide resin and a compound represented by the general formula (I): (Where A is a group Is a group which forms a heterocyclic ring composed of 5 or 6 atoms together with a single bond or a double bond.
Or three carbon atoms, two or three carbon atoms forming part of one aromatic ring, two nitrogen atoms connected by a single or double bond, or One carbon atom connected by a bond or a double bond to one
Has a main chain of one or two nitrogen atoms, and X is an oxygen atom, a sulfur atom, a carbon atom or a nitrogen atom, wherein the carbon atom or the nitrogen atom is a hydrogen atom,
Which is substituted with an alkyl group, a phenyl group or a mercapto group). 2. The heat-resistant resin composition according to claim 1, comprising 0.01 to 20 parts by weight of the heterocyclic mercaptan represented by the general formula (I) based on 100 parts by weight of the polyamideimide resin. 3. The method according to claim 1, wherein the heterocyclic mercaptan represented by the general formula (I) is 2-amino-5-mercapto-1,3,4.
The heat-resistant resin composition according to claim 1, which is -thiadiazole. 4. The heat-resistant resin composition according to claim 1, wherein the heterocyclic mercaptan represented by the general formula (I) is a 2-mercaptobenzothiazolecyclohexylamine salt. 5. The heat resistance according to claim 1, wherein the heterocyclic mercaptan represented by the general formula (I) is 2-di-n-butylamino-4,6-dimercapto-1,3,5-triazine. Resin composition. 6. The polyamide imide resin having a number average molecular weight of 10,000 to 50,000.
The heat-resistant resin composition according to 2, 3, 4 or 5. 7. A paint comprising the heat-resistant resin composition according to claim 1, 2, 3, 4, 5, or 6 as a coating film component. 8. An enameled wire formed by using the paint according to claim 7 to form a film.